December 13, 2013

First Ever Soft-Tissue Crest Discovered On Dinosaur Fossil

Researchers from Australia's University of New England (UNE) and Italy’s University of Bologna have reportedly discovered the first evidence that dinosaurs had fleshy head ornaments similar to a rooster’s comb.

As the study authors report in Thursday’s edition of the journal Current Biology, they discovered the head crest on a rare, mummified specimen of the duck-billed dinosaur known as Edmontosaurus regalis that was discovered in Alberta, Canada.

These dinosaurs roamed the land in North America between 65 million and 75 million years ago, the researchers said. They were approximately 12 meters long and filled an ecological role similar to that filled by modern-day deer or kangaroos. However, little did the scientists know that they had fleshy structures on their heads.

In fact, UNE paleontologist Phil Bell told National Geographic’s Sandeep Ravindran that the ornament was so unexpected that he wound up putting a chisel right through the middle of it. “I was just expecting there to be rock, and all of a sudden there was skin underneath,” he recalled.

Quite by accident, Bell had discovered the first dinosaur fossil adorned with a fleshy crest on top of its head. “We know that lots of dinosaurs had different kinds of head ornaments, but these are all made of bones,” he explained. “There’s never been any indication that any dinosaurs had something like this, so this was totally out of left field.”

Bell and Federico Fanti, a post-doctoral researcher at the University of Bologna’s Department of Biological, Geological and Environmental Sciences, found the specimen in deposits located west of the city of Grande Prairie in west-central Alberta. Even before they knew about the crest, they knew the fossil was special because of the presence of skin impressions on parts of the mummified body.

“This is the first evidence of an entirely soft-tissue crest for any dinosaur. Bony crests are well known but skin rarely fossilizes and even when it does, it is almost never found on the skull," Bell told BBC Nature reporter Ella Davies. “While we were using a rock saw to cut the block down in the field to make it easier to transport, we discovered skin impressions quite by accident but it wasn't until we got the block back to the lab that we realized just how extensive the skin was.”

The presence of the scaly, flesh structure on this fossil “raises the thought-provoking possibility of similar crests among other dinosaurs,” he added. “Based on comparisons with living birds, crests like that in Edmontosaurus were probably used to attract mates. Often, the largest and most brightly colored crest gets the girl and in the case of herding animals, it probably identified who was the head of the group.”